Urban Salvation: As Waste Streams Grow and Natural Resources Dwindle, Demand for Salvaged Materials Will Rise

Article excerpt

WE ARE SURROUNDED by a sea of discarded materials that can be reused in building construction. Think of all those political signboards that we see at election time outside private houses and in other prominent locations. Temporary signs are often made of corrugated plastic that could be used as siding or insulation.

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Despite the opportunities to reuse discarded materials, construction and demolition leftovers make up about 35 per cent of the total waste stream in Canada. Meanwhile, the growing worldwide demand for new construction materials is putting so much pressure on natural resources that Worldwatch Institute estimates that by the year 2030, the world will have run out of many of them. At that point, building with salvaged goods and "waste" diverted from landfill won't be the exception; it will be the norm.

At present, aluminum may come from South America, steel from Russia, glass from China and marble from Italy. We think nothing of transporting these materials over long distances even when they may be available from a local source at what could be a better price. In a post-peak-oil world, however, bulky construction materials from afar may be far more costly and their supply vastly reduced.

Some in the construction industry are beginning to recognize that in the future the key drivers for building construction and possibly even design will be closed-loop systems that use local, readily available, renewable or reused resources. In fact, green-building rating systems such as LEED already encourage such practice.

Reusing materials is actually centuries old. Medieval buildings in Europe were often constructed from stone taken from ruins of Roman buildings. The lovely Tweedsmuir church in Orangeville, Ontario, is but one wartime example. It is constructed of stone salvaged when Canada Portland tore down its nearby cement factory in 1940. Boards removed from old barns in Eastern Canada have long been used as siding on homes, and builders dismantled many of Canada's grain elevators on the treeless Prairies to salvage the old timber.

More exotic examples include Michael Reynolds' Earthship buildings. He filled old car tires and beverage containers with compacted earth to construct the walls of buildings. And students involved with Rural Studio erected a variety of buildings for disadvantaged communities in Alabama mainly using locally available waste and surplus materials.

These examples are mostly ad hoc projects. A few architects, however, are interested in the creative and environmental opportunities offered by using materials sourced from local waste streams and regional renewable resources in mainstream buildings.

Mountain Equipment Coop (MEC), the environmentally conscious retailer of outdoor recreational gear, leads the charge in this practice, having used the components of old buildings in its Ottawa (2000) and Winnipeg (2002) stores. The site for their retail operation in the nation's capital was occupied for 40 years by a grocery store. MEC couldn't reuse the supermarket, but the company carefully dismantled and catalogued all the store's components. MEC's architects then designed its new building around what was available, using about 75 per cent of the stockpile, including the structural grid, footings and components of the steel frame. In fact, the characteristics of the old supermarket dictated the layout, aesthetics and performance of the new store.

The Vancouver-based architectural firm Busby and Associates (now Busby Perkins and Will) used a similar process for the City of Vancouver's materials testing facility (1999). Approximately three-quarters of the building's structure and fabric consists of salvaged and recycled materials, including heavy timber structural members, roof trusses, existing lab and mechanical equipment, light fixtures and furniture. They even fabricated custom components such as windows by inserting glass into frames milled on site from old wood decking. …